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Problem 1.3.33
Determine whether the survey question is biased. If the question is biased, suggest a better wording.
How much do you exercise during an average week?
Problem 1.1.13
"Determine whether the data set is a population or a sample. Explain your reasoning.
A survey of 250 members from an organized union of over 20,000 members"
Problem 1.3.13
Determine whether the study is an observational study or an experiment. Explain.
A study used periodic blood pressure readings and brain MRIs of adults to find that adults with long periods of high blood pressure were more likely to develop cerebral small blood vessel disease. (Source: American Heart Association)
Problem 1.1.48
A study showed an association between intentional weight loss and a decreased risk of high blood pressure. Is it appropriate to infer from this study that weight loss causes a decreased risk of high blood pressure? Explain. (Source: European Association for the Study of Obesity)
Problem 1.1.47
A study showed the same level of T cell production in senior citizens who are amateur cyclists as in young adults, but a significantly lower level of T cell production in senior citizens who do not exercise regularly. Is it appropriate to infer that exercise stimulates T cell production? Explain. (Source: University of Birmingham)
Problem 1.2.17
Determine the level of measurement of the data set. Explain your reasoning.
The lengths (in centimeters) of 22 Ford automobiles are listed. (Source: Automobiledimension.com)
404 407 410 416 421 438 440 443 461 467 471 478 480 483 483 485 487 487 497 505 534 536
Problem 1.3.25
"Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.
After a hurricane, a disaster area is divided into 200 equal grids. Thirty of the grids are selected, and every occupied household in the grid is interviewed to help focus relief efforts on what residents require the most."
Problem 1.3.24
Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.
Questioning university students as they leave a college cafeteria, a researcher asks 342 students about their eating habits.
Problem 1.1.33
"Identify the population and the sample. Describe the sample data set.
To gather information about starting salaries at companies listed in the Standard & Poor’s 500, a researcher contacts 74 of the 500 companies."
Problem 1.2.19
"Determine the level of measurement of the data set. Explain your reasoning.
The top ten fiction hardcover books on The New York Times Best Sellers List based on sales in the week ending March 6, 2021, are listed. (Source: The New York Times)
1. Life After Death
2. The Four Winds
3. Klara and the Sun
4. Dark Sky
5. The Affair
6. The Midnight Library
7. The Lost Apothecary
8. The Vanishing Half
9. Infinite Country
10. A Court of Silver Flames"
Problem 1.1.2
Why is a sample used more often than a population?
Problem 1.3.27
Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.
Soybeans are planted on a 48-acre field. The field is divided into one-acre subplots. A sample is taken from each subplot to estimate the harvest.
Problem 1.2.1
Name each level of measurement for which data can be qualitative.
Problem 1.1.17
Determine whether the data set is a population or a sample. Explain your reasoning.
The number of guests in each room of a hotel
Problem 1.3.30
Determine whether you would take a census or use a sampling. If you would use a sampling, determine which sampling technique you would use. Explain.
The average distance traveled to a stadium by 55,000 spectators
Problem 1.1.36
Determine whether the number describes a population parameter or a sample statistic. Explain your reasoning.
A survey of 919 college board members found that 89% think that their institution is a good place for members of racial and ethnic minorities. (Source: Association of Governing Boards of Universities and Colleges)
Problem 1.2.25
The items below appear on a physician’s intake form. Determine the level of measurement of the data for each category.
a. Temperature
b. Allergies
c. Weight
d. Pain level (scale of 0 to 10)
Problem 1.3.2
What is the difference between a census and a sampling?
Problem 1.2.32
"Determine whether the data are qualitative or quantitative, and determine the level of measurement of the data set.
The numbers of performances for the 10 longest-running original runs of Broadway shows as of March 15, 2020, are listed. (Source: Playbill)
13,370 9692 9302 7485 6836 6680 6137 5959 5758 5461"
Problem 1.1.40
Determine whether the number describes a population parameter or a sample statistic. Explain your reasoning.
Voter registration records show that 47% of all voters in a county are registered as Democrats.
Problem 1.1.11
"Determine whether the data set is a population or a sample. Explain your reasoning.
The salary of each employee of an advertising firm"
Problem 1.2.7
Determine whether the data are qualitative or quantitative. Explain your reasoning.
Nationalities of passengers on a plane
Problem 1.3.6
Determine whether the statement is true or false. If it is false, rewrite it as a true statement.
A double-blind experiment is used to increase the placebo effect.
Problem 1.CR.9
In Exercises 9 and 10, determine whether the study is an observational study or an experiment. Explain.
To study the effect of using digital devices in the classroom on exam performance, researchers divided 726 undergraduate students into three groups, including a group that was allowed to use digital devices, a group that had restricted access to tablets, and a control group that was “technologyfree.” (Source: Massachusetts Institute of Technology)
Problem 1.CR.4
In Exercises 4 and 5, determine whether the number is a parameter or a statistic. Explain your reasoning.
In 2021, the median annual salary of a first-year chemist was $58,700.
Problem 1.CR.12
In Exercises 11 and 12, determine whether the data are qualitative or quantitative, and determine the level of measurement of the data set.
The six top-earning states in 2019 by median household income are listed. (Source: U.S. Census Bureau)
1. Maryland 2. New Jersey 3. Hawaii
4. Massachusetts 5. Connecticut 6. Alaska
Problem 1.Q.8
Which technique used in Exercise 7 could lead to a biased study? Explain.
Problem 1.Q.4b
Determine the level of measurement of the data set. Explain your reasoning.
The horsepowers of racing car engines
Problem 1.Q.7c
Identify the sampling technique used in each study. Explain your reasoning.
A study on attitudes about smoking is conducted at a college. The students are divided by class (freshman, sophomore, junior, and senior). Then a random sample is selected from each class and interviewed.
Problem 1.Q.6
An experiment is performed to test the effects of a new drug on attention-deficit/hyperactivity disorder (ADHD). The experimenter identifies 320 people ages 7 to 44 with ADHD to participate in the experiment. The subjects are divided into equal groups according to age. Within each group, subjects are then randomly selected to be in either the treatment group or the control group. What type of experimental design is being used for this experiment?